Steve Jobs died regretting that he had spent so long attempting to treat his cancer with alternative medicine before agreeing to undergo surgery, his biographer has disclosed.

The Apple chief executive, who died this month after a pancreatic tumour spread elsewhere, delayed having operations and chemotherapy for nine months after the disease was discovered in October 2003.

In spite of pleas from family and friends, he tried to cure himself through acupuncture sessions, drinking special fruit juices, visiting "spiritualists" and using other treatments he found on the internet.

Some cancer experts have said that Mr Jobs may have extended his life or even survived if he had promptly tackled his cancer aggressively with scientifically proven medical treatments.

Walter Isaacson, whose much-anticipated authorised book on Mr Jobs's life is to be released later this month, said that before he died the 56-year-old had come to realise that he had made a mistake.

"We talked about this a lot," Isaacson told a television interview. "He wanted to talk about it, how he regretted it. I think he felt he should have been operated on sooner."

Asked why "such a smart man could do such a stupid thing", Isaacson said: "I think he felt: if you ignore something you don't want to exist, you can have magical thinking. It had worked for him in the past. He would regret it."

Mr Jobs's wife, Laurene Powell, told the biographer: "The big thing was he really was not ready to open his body. It's hard to push someone to do that." She pleaded: "The body exists to serve the spirit".

Isaacson states in the book that several other Jobs confidantes, including Mona Simpson, his sister, and Art Levinson, an Apple board member, pushed him to embrace conventional medicine. "I told him he was crazy," said Andrew Grove, the former head of the computer chip company Intel.

When he eventually agreed to treatment, Mr Jobs went to great expense to ensure that he was given the most pioneering work available, Isaacson writes, having his DNA sequenced for $100,000 (£62,000).

Isaacson, who interviewed Mr Jobs more than 40 times over two years, states that this allowed Mr Jobs's doctors to tailor his drugs to target defective molecular pathways in his body. But eventual surgery revealed that the cancer had spread to tissue surrounding his pancreas.

The book also discloses that Mr Jobs had bad-tempered run-ins with Barack Obama and his advisers, including a meeting last autumn when he told Mr Obama: "You're headed for a one-term presidency."

Mr Jobs told him that the US was too unfriendly to business, and that companies would rather build factories in China than in America, where they were frustrated by "regulations and unnecessary costs".

Apple and Mr Jobs have frequently been criticised for having their products manufactured in Chinese plants with poor pay for employees and controversial working conditions.

The Apple chief also criticised America's uncompetitive education system, which he said was "crippled by union work rules." He said Mr Obama should have schools open until 6pm, 11 months a year.

The meeting, which took place at a hotel near San Francisco Airport, almost did not take place at all because Mr Jobs insisted on receiving a personal invitation from Mr Obama, the book discloses.

Mr Jobs also came close to backing out of another meeting, in February this year at the White House, when too many other technology company chief executives were invited as well.

He told friends the menu for the dinner meeting – prawn, cod and lentil salad, and chocolate truffle dessert – was "too fancy". He eventually relented and was pictured sitting beside Mr Obama, who was flanked on his other side by Mark Zuckerberg of Facebook.

The book also discloses that contrary to popular belief Mr Jobs, who was adopted, did in fact meet his estranged biological father, Abdulfattah Jandali.

Mr Jobs had been a customer at Mr Jandali's Mediterranean restaurant, near San Jose, without realising that it was owned by his father. "It was amazing," he told Isaacson. "I had been to that restaurant a few times, and I remember meeting the owner. He was Syrian. Balding. We shook hands." However, Mr Jobs said he had no desire to see him again. "I was a wealthy man by then," he told the biographer. "I didn't trust him not to try to blackmail me or go to the press about it."